U.S. patent application number 13/807622 was filed with the patent office on 2013-04-18 for electrode assembly comprising fiber-shaped structures.
This patent application is currently assigned to SHINE CO., LTD. The applicant listed for this patent is Kwon Seok Kim. Invention is credited to Kwon Seok Kim.
Application Number | 20130095367 13/807622 |
Document ID | / |
Family ID | 45032640 |
Filed Date | 2013-04-18 |
United States Patent
Application |
20130095367 |
Kind Code |
A1 |
Kim; Kwon Seok |
April 18, 2013 |
ELECTRODE ASSEMBLY COMPRISING FIBER-SHAPED STRUCTURES
Abstract
The present invention relates to an electrode assembly
comprising fiber-shaped structures. The electrode assembly for a
battery according to one embodiment of the present invention
comprises: a first electrode including a plurality of first
fiber-shaped structures extending in a first direction; a second
electrode including a plurality of second fiber-shaped structures
which extend in a second direction other than the first direction,
and the polarities of which are different from the polarities of
the first structures; and a first separator film interposed between
the first structures and the second structures which intersect with
each other, so as to separate the first structures and the second
structures from each other.
Inventors: |
Kim; Kwon Seok; (Seoul,
KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Kim; Kwon Seok |
Seoul |
|
KR |
|
|
Assignee: |
SHINE CO., LTD
Busan
KR
|
Family ID: |
45032640 |
Appl. No.: |
13/807622 |
Filed: |
July 1, 2011 |
PCT Filed: |
July 1, 2011 |
PCT NO: |
PCT/KR2011/004851 |
371 Date: |
December 28, 2012 |
Current U.S.
Class: |
429/149 ;
429/211; 429/246 |
Current CPC
Class: |
H01M 4/13 20130101; H01M
4/72 20130101; H01M 10/0436 20130101; H01M 4/00 20130101; H01M 4/74
20130101; H01M 2/1673 20130101; H01M 4/806 20130101; Y02E 60/10
20130101; H01M 2004/025 20130101; H01M 4/70 20130101 |
Class at
Publication: |
429/149 ;
429/246; 429/211 |
International
Class: |
H01M 4/00 20060101
H01M004/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 2, 2010 |
KR |
10-2010-0064132 |
Claims
1. An electrode assembly comprising: a first electrode comprising a
plurality of first structures that have fibrous shape and extend in
a first direction; a second electrode comprising a plurality of
second structures that have fibrous shape and polarity opposite to
polarity of the first structures, and extend in a second direction
different from the first direction; and a first separator that is
disposed between the first structures and the second structures
which cross each other, and separates the first structures from the
second structures.
2. The electrode assembly of claim 1, wherein the first structures
extend on a first main surface of the first separator to be spaced
apart from one another, and the second structures extend on a
second main surface of the first separator which is opposite to the
first main surface to be spaced apart from one another.
3. The electrode assembly of claim 2, further comprising: a third
electrode comprising a plurality of third structures that have
fibrous shape and polarity opposite to the polarity of the first
structures, and extend on the first main surface of the first
separator in the first direction to alternate with the first
structures; and a fourth electrode comprising a plurality of fourth
structures that have fibrous shape and polarity opposite to the
polarity of the second structures, and extend on the second main
surface of the first separator in the second direction to alternate
with the second structures, wherein the third structures and the
fourth structures which cross each other are separated from each
other by the first separator.
4. The electrode assembly of claim 3, wherein at least some of the
first through fourth structures are partially or totally buried in
the first or second main surface of the first separator.
5. The electrode assembly of claim 1, further comprising: at least
one second separator that is stacked on the first separator to form
a multi-layered structure; and a third electrode comprising a
plurality of third structures that extend on a main surface of the
second separator which is opposite to an interface between the
first separator and the second isolation, and have fibrous shape
and polarity opposite to polarity of structures of the interface,
wherein the third structures and the structures on the interface
cross each other.
6. The electrode assembly of claim 3, further comprising: at least
one second separator that is stacked on the first separator to form
a multi-layered structure; a fifth electrode comprising a plurality
of fifth structures that extend on a main surface of the second
separator which is opposite to an interface between the first
separator and the second separator, and have fibrous shape and
polarity opposite to polarity of structures on the interface,
wherein the fifth structures and the structures on the interface
cross each other; and a sixth electrode comprising a plurality of
sixth structures that have fibrous shape and polarity opposite to
the polarity of the fifth structures, extend on the other main
surface of the second separator to alternate with the fifth
structures, wherein the sixth structures and the structures on the
interface cross each other.
7. The electrode assembly of claim 6, wherein at least some of the
first through sixth structures are partially or totally buried in
the first or second separator.
8. The electrode assembly of claim 1, wherein the first structures
and the second structures cross each other as weft threads and warp
threads reciprocating through the first separator.
9. The electrode assembly of claim 1, wherein each of the first
structures and the second structures comprises a current collector
core and an active material layer that surrounds the current
collector core.
10. The electrode assembly of claim 9, wherein only ones of the
first structures and the second structures selectively further
comprise a solid electrolyte layer that surrounds the active
material layer.
11. The electrode assembly of claim 1, wherein a thickness of each
of the first and second structures ranges from 400 .mu.m to 2,000
.mu.m, and a distance between the first and second structures
ranges from 2 .mu.m to 400 .mu.m.
12. The electrode assembly of claim 1, wherein a distance between
the first and second structures is less than a thickness of each of
the first and second structures.
13. The electrode assembly of claim 1, wherein the first separator
comprises any one of a micro-porous film, a woven fabric, a
nonwoven fabric, an intrinsic solid polymer electrolyte film, a gel
solid polymer electrolyte film, and a combination thereof.
14-19. (canceled)
20. An electrode assembly comprising: an isolation matrix; a first
electrode comprising a plurality of first structures that have
fibrous shape, and pass through the isolation matrix and extend on
a first plane in the isolation matrix in a first direction to be
spaced apart from one another; and a second electrode comprising a
plurality of second structures that have fibrous shape, and pass
through the isolation matrix and extend on a second plane, which is
spaced apart from the first plane to be parallel to the first
plane, in the isolation matrix in a second direction different from
the first direction to cross the first structures.
21. The electrode assembly of claim 20, further comprising: a third
electrode comprising a plurality of third structures that have
fibrous shape and polarity opposite to polarity of the first
structures, and extend on the first plane in the first direction to
alternate with the first structures; and a fourth electrode
comprising a plurality of fourth structures that have fibrous shape
and polarity opposite to polarity of the second structures, and
extend on the second plane in the second direction to alternate
with the second structures.
22. The electrode assembly of claim 20, wherein a plurality of the
first planes and a plurality of the second planes are provided to
form a multi-layered structure.
23. The electrode assembly of claim 20, wherein each of the first
structures and the second structures comprises a current collector
core and an active material layer that surrounds the current
collector core.
24. The electrode assembly of claim 20, wherein only ones of the
first structures and the second structures selectively further
comprise a solid electrolyte layer that surrounds the active
material layer.
25. The electrode assembly of claim 20, wherein the isolation
matrix is any one of a micro-porous film, a woven fabric, a
nonwoven fabric, an intrinsic solid polymer electrolyte film, a gel
solid polymer electrolyte film, and a combination thereof.
26. The electrode assembly of claim 20, wherein a thickness of each
of the first and second structures ranges from 400 .mu.m to 2,000
.mu.m, and a distance between the first and second structures
ranges from 2 .mu.m to 400 .mu.m.
27. The electrode assembly of claim 20, wherein a distance between
the first and second structures is less than a thickness of each of
the first and second structures.
28. An electrode assembly comprising: an isolation matrix; a first
electrode comprising a plurality of first structures that have
fibrous shape, and pass through the isolation matrix and extend on
a first plane in the isolation matrix in a first direction to be
spaced apart from one another; and a second electrode comprising a
plurality of second structures that have fibrous shape, and pass
through the isolation matrix and extend on the first plane in a
second direction different from the first direction such that the
second structures and the first structures cross each other as weft
threads and warp threads.
29. The electrode assembly of claim 28, further comprising a second
cathode and a second anode respectively comprising a plurality of
third structures and a plurality of fourth structures which have
fibrous shapes and extend on a second plane, which is spaced apart
from the first plane to be parallel to the first plane, in the
isolation matrix such that the third and fourth structures and the
first and second structures cross each other as weft threads and
warp threads.
30. The electrode assembly of claim 28, wherein each of the first
structures and the second structures comprises a current collector
core and an active material that surrounds the current collector
core.
31. The electrode assembly of claim 28, wherein only ones of the
first structures and the second structures selectively further
comprise a solid electrolyte layer that surrounds the active
material layer.
32. The electrode assembly of claim 28, wherein the isolation
matrix comprises an intrinsic solid polymer electrolyte film or a
gel solid polymer electrolyte film.
33. The electrode assembly of claim 28, wherein a thickness of each
of the first and second structures ranges from 400 .mu.m to 2,000
.mu.m, and a distance between the first and second structures
ranges from 2 .mu.m to 400 .mu.m.
34. The electrode assembly of claim 28, wherein a distance between
the first and second structures is less than a thickness of the
first and second structures.
35. An electrode assembly comprising: a first electrode comprising
a plurality of first structures that have fibrous shapes and extend
in a first direction; a second electrode that has a planar shape
and a polarity opposite to polarities of the first structures; and
a separator that is disposed between the first electrode and the
second electrode.
36. The electrode assembly of claim 35, further comprising a third
electrode comprising a plurality of second structures that have
fibrous shape and the same polarity as the polarity of the first
structures, and extend in a second direction different from the
first direction to cross the first structures.
37. The electrode assembly of claim 36, wherein the first
structures and the second structures cross each other as weft
threads and warp threads.
38. The electrode assembly of claim 37, wherein the first and
second structures reciprocate through the separator.
39. The electrode assembly of claim 35, wherein the first
structures further extend to surround both main surfaces of the
second electrode.
40. The electrode assembly of claim 35, wherein a thickness of each
of the first structures ranges from 400 .mu.m to 2,000 .mu.m, and a
distance between the first structures ranges from 2 .mu.m to 400
.mu.m.
41. The electrode assembly of claim 35, wherein a distance between
the first structures is less than a thickness of each of the first
structures.
42. The electrode assembly of claim 1, wherein the first electrode
further comprises a plurality of third structures that have fibrous
shape and the same polarity as polarity of the first structures and
extend in a third direction different from the first direction to
cross the first structures, and the second electrode further
comprises a plurality of fourth structures that have fibrous shape
and the same polarity as polarity of the second structures and
extend in a fourth direction different from the second direction to
cross the third structures.
43. The electrode assembly of claim 42, wherein the first electrode
and the second electrode are rotated or offset such that the first
electrode and the second electrode are not symmetrical with each
other.
44. The electrode assembly of claim 42, wherein the first and third
structures cross each other as weft threads and warp threads, and
the second and fourth structures cross each other as weft threads
and warp threads.
45. The electrode assembly of claim 42, wherein each of the first
through fourth structures comprises a current collector core and an
active material layer that surrounds the current collector core.
Description
TECHNICAL FIELD
[0001] The present invention relates to a battery technology, and
more particularly, to an electrode assembly of a battery including
fibrous structures.
BACKGROUND ART
[0002] As a semiconductor manufacturing technology and a
communication technology have recently been developed, the mobile
electronic device industry has expanded, and demands for
environmental preservation and development of alternative energy
due to resource depletion have increased, batteries have been
actively studied. Since lithium primary batteries which are
representative batteries have a higher voltage and higher energy
density than conventional aqueous batteries, the lithium primary
batteries may be easily made compact and light. Such lithium
primary batteries are widely used, for example, as main power
supply sources for mobile electronic devices or backup power supply
sources.
[0003] Secondary batteries are rechargeable batteries formed of an
electrode material having high reversibility. The secondary
batteries are classified into cylindrical secondary batteries and
polygonal secondary batteries according to outer appearances, and
classified into nickel/metal hydride (Ni-MH) secondary batteries,
lithium (Li) secondary batteries, and lithium-ion (Li-ion)
secondary batteries according to anode and cathode materials.
Devices to which secondary batteries are applied have been
diversified from small batteries such as mobile phones, notebooks,
and mobile displays to medium and large batteries for electric
vehicles and hybrid vehicles. Accordingly, batteries are required
to have high stability and cost effectiveness as well as
lightweight design, high energy density, high charge/discharge
speed, high charge/discharge efficiency, and excellent cycle
characteristics.
DISCLOSURE OF THE INVENTION
Technical Problem
[0004] The present invention provides an electrode assembly of a
battery which has high energy density, high charge/discharge
efficiency, and excellent cycle characteristics and whose shape and
capacity may be easily adjusted.
Technical Solution
[0005] According to an aspect of the present invention, there is
provided an electrode assembly including: a first electrode
including a plurality of first structures that have fibrous shape
and extend in a first direction; a second electrode including a
plurality of second structures that have fibrous shape and polarity
opposite to polarities of the first structures, and extend in a
second direction different from the first direction; and a first
separator that is disposed between the first structures and the
second structures which cross each other, and separates the first
structures from the second structures.
[0006] The first structures may extend on a first main surface of
the first separator to be spaced apart from one another, and the
second structures may extend on a second main surface of the first
separator which is opposite to the first main surface to be spaced
apart from one another. The electrode assembly may further include:
a third electrode including a plurality of third structures that
have fibrous shape and polarity opposite to the polarity of the
first structures, and extend on the first main surface of the first
separator in the first direction to alternate with the first
structures; and a fourth electrode including a plurality of fourth
structures that have fibrous shape and polarity opposite to the
polarity of the second structures, and extend on the second main
surface of the first separator in the second direction to alternate
with the second structures, wherein the third structures and the
fourth structures which cross each other are separated from each
other by the first separator.
[0007] At least some of the first through fourth structures may be
partially or totally buried in the first or second main surface of
the first separator. The electrode assembly may further include: at
least one second separator that is stacked on the first separator
to form a multi-layered structure; and a third electrode including
a plurality of third structures that extend on a main surface of
the second separator which is opposite to an interface between the
first separator and the second isolation, and have fibrous shape
and polarity opposite to polarity of structures of the interface,
wherein the third structures and the structures on the interface
cross each other.
[0008] The electrode assembly may further include: at least one
second separator that is stacked on the first separator to form a
multi-layered structure; a fifth electrode including a plurality of
fifth structures that extend on a main surface of the second
separator which is opposite to an interface between the first
separator and the second separator, and have fibrous shape and
polarity opposite to polarity of structures on the interface,
wherein the fifth structures and the structures on the interface
cross each other; and a sixth electrode including a plurality of
sixth structures that have fibrous shape and polarity opposite to
the polarity of the fifth structures, extend on the other main
surface of the second separator to alternate with the fifth
structures, wherein the sixth structures and the structures on the
interface cross each other. At least some of the first through
sixth structures may be partially buried in the first or second
separator.
[0009] The first structures and the second structures may cross
each other as weft threads and warp threads reciprocating through
the first separator. Each of the first structures and the second
structures may include a current collector core and an active
material layer that surrounds the current collector core. Only ones
of the first structures and the second structures may selectively
further include a solid electrolyte layer that surrounds the active
material layer.
[0010] A thickness of each of the first and second structures may
range from 400 .mu.m to 2,000 .mu.m, and a distance between the
first and second structures may range from 2 .mu.m to 400 .mu.m. A
distance between the first and second structures may be less than a
thickness of each of the first and second structures. The first
separator may include any one of a micro-porous film, a woven
fabric, a nonwoven fabric, an intrinsic solid polymer electrolyte
film, a gel solid polymer electrolyte film, and a combination
thereof. The electrode assembly may be used for a primary battery
or a secondary battery.
[0011] According to another aspect of the present invention, there
is provided an electrode assembly including: a first electrode
including a plurality of first structures that have fibrous shape
and extend in a first direction, and a plurality of second
structures that have fibrous shape and the same polarity as
polarity of the first structures and extend in a second direction
different from the first direction to cross the first structures; a
second electrode including a plurality of third structures that
have fibrous shape and extend in a third direction, and a plurality
of fourth structures that have fibrous shape and the same polarity
as polarities of the third structures and extend in a fourth
direction different from the third direction to cross the third
structures; and a first separator that separates the first
electrode from the second electrode.
[0012] The first electrode and the second electrode may be rotated
or offset such that the first electrode and the second electrode
are not symmetrical with each other. The first and second
structures may cross each other as weft threads and warp threads,
and the third and fourth structures may cross each other as weft
threads and warp threads. Each of the first structures and the
second structures may include a current collector core and an
active material layer that surrounds the current collector core.
Only one of a group of the first and second structures and a group
of the third and fourth structures may selectively further include
a solid electrolyte layer.
[0013] According to another aspect of the present invention, there
is provided an electrode assembly including: an isolation matrix; a
first electrode including a plurality of first structures that have
fibrous shape, and pass through the isolation matrix and extend on
a first plane in the isolation matrix in a first direction to be
spaced apart from one another; and a second electrode including a
plurality of second structures that have fibrous shape, and pass
through the isolation matrix and extend on a second plane, which is
spaced apart from the first plane to be parallel to the first
plane, in the isolation matrix in a second direction different from
the first direction to cross the first structures.
[0014] The electrode assembly may further include a third electrode
including a plurality of third structures that have fibrous shape
and polarity opposite to polarity of the first structures, and
extend on the first plane in the first direction to alternate with
the first structures; and a fourth electrode including a plurality
of fourth structures that have fibrous shape and polarity opposite
to polarity of the second structures, and extend on the second
plane in the second direction to alternate with the second
structures. A plurality of the first planes and a plurality of the
second planes may be provided to form a multi-layered
structure.
[0015] Each of the first structures and the second structures may
include a current collector core and an active material layer that
surrounds the current collector core. Only ones of the first
structures and the second structures may selectively further
include a solid electrolyte layer that surrounds the active
material layer.
[0016] The isolation matrix may be any one of a micro-porous film,
a woven fabric, a nonwoven fabric, an intrinsic solid polymer
electrolyte film, a gel solid polymer electrolyte film, and a
combination thereof. A thickness of each of the first and second
structures may range from 400 .mu.m to 2,000 .mu.m, and a distance
between the first and second structures may range from 2 .mu.m to
400 .mu.m. A distance between the first and second structures may
be less than a thickness of each of the first and second
structures.
[0017] According to another aspect of the present invention, there
is provided an electrode assembly including: an isolation matrix; a
first electrode including a plurality of first structures that have
fibrous shape, and pass through the isolation matrix and extend on
a first plane in the isolation matrix in a first direction to be
spaced apart from one another; and a second electrode including a
plurality of second structures that have fibrous shape, and pass
through the isolation matrix and extend on the first plane in a
second direction different from the first direction such that the
second structures and the first structures cross each other as weft
threads and warp threads.
[0018] The electrode assembly may further include a second cathode
and a second anode respectively including a plurality of third
structures and a plurality of fourth structures which have fibrous
shapes and extend on a second plane, which is spaced apart from the
first plane to be parallel to the first plane, in the isolation
matrix such that the third and fourth structures and the first and
second structures cross each other as weft threads and warp
threads. Each of the first structures and the second structures may
include a current collector core and an active material that
surrounds the current collector core. Only ones of the first
structures and the second structures may selectively further
include a solid electrolyte layer that surrounds the active
material layer.
[0019] The isolation matrix may include an intrinsic solid polymer
electrolyte film or a gel solid polymer electrolyte film. A
thickness of each of the first and second structures may range from
400 .mu.m to 2,000 .mu.m, and a distance between the first and
second structures may range from 2 .mu.m to 400 .mu.m. A distance
between the first and second structures may be less than a
thickness of the first and second structures.
[0020] According to another aspect of the present invention, there
is provided an electrode assembly including: a first electrode
including a plurality of first structures that have fibrous shapes
and extend in a first direction; a second electrode that has a
planar shape and a polarity opposite to polarities of the first
structures; and a separator that is disposed between the first
electrode and the second electrode.
[0021] The electrode assembly may further include a third electrode
including a plurality of second structures that have fibrous shape
and the same polarity as the polarity of the first structures, and
extend in a second direction different from the first direction to
cross the first structures. The first structures and the second
structures may cross each other as weft threads and warp threads.
The first and second structures may reciprocate through the
separator.
[0022] The first structures may further extend to surround both
main surfaces of the second electrode. A thickness of each of the
first structures may range from 400 .mu.m to 2,000 .mu.m, and a
distance between the first structures may range from 2 .mu.m to 400
.mu.m. A distance between the first structures may be less than a
thickness of each of the first structures.
[0023] The present also provides a battery having the electrode
assembly. The battery having the electrode assembly may be a
primary battery or a secondary battery.
Advantageous Effects
[0024] According to the one or more embodiments of the present
invention, since at least some electrodes include a plurality of
structures having fibrous shapes, an interfacial surface area
between the electrodes may be increased due to curved surfaces and
3D arrangements of the structures. Accordingly, battery energy
density in the same volume may be improved, and charge/discharge
speed, charge/discharge efficiency, and battery cycle
characteristics may also be improved.
[0025] Also, since fibrous structures constitute electrodes, a
shape of a battery may be easily changed. Since capacity may be
easily adjusted by bending or stacking the battery, the battery may
be easily used as a small battery or a large or medium battery.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a perspective view illustrating an electrode
assembly of a battery, according to an embodiment of the present
invention;
[0027] FIG. 2 is a perspective cross-sectional view illustrating
fibrous structures, according to other embodiment of the present
invention;
[0028] FIG. 3 is a perspective view illustrating an electrode
assembly of a battery, according to another embodiment of the
present invention;
[0029] FIG. 4 is an exploded perspective view illustrating an
electrode assembly of a battery, according to another embodiment of
the present invention;
[0030] FIG. 5 is an exploded perspective view illustrating an
electrode assembly of a battery, according to another embodiment of
the present invention;
[0031] FIGS. 6A through 6C are perspective views illustrating an
electrode assembly according to another embodiment of the present
invention;
[0032] FIG. 7 is a perspective view illustrating an electrode
assembly of a battery, according to another embodiment of the
present invention;
[0033] FIG. 8 is a perspective view illustrating an electrode
assembly according to another embodiment of the present
invention;
[0034] FIG. 9 is a perspective view illustrating an electrode
assembly according to another embodiment of the present
invention;
[0035] FIG. 10 is a perspective view illustrating an electrode
assembly according to another embodiment of the present
invention;
[0036] FIG. 11 is a perspective view illustrating an electrode
assembly according to another embodiment of the present
invention;
[0037] FIG. 12 is a perspective view illustrating an electrode
assembly according to another embodiment of the present invention;
and
[0038] FIG. 13 is a perspective view illustrating an electrode
assembly according to another embodiment of the present
invention.
MODE FOR CARRYING OUT THE INVENTION
[0039] The present invention will now be described more fully with
reference to the accompanying drawings, in which exemplary
embodiments of the invention are shown.
[0040] The present invention now will be described more fully
hereinafter with reference to the accompanying drawings, in which
elements of the invention are shown. The present invention may,
however, be embodied in many different forms and should not be
construed as limited to the exemplary embodiments set forth herein.
Rather, these embodiments are provided so that this disclosure will
be thorough and complete, and will fully convey the scope of the
present invention to one of ordinary skill in the art.
[0041] Also, in the drawings, thicknesses or sizes of layers are
exaggerated for convenience of explanation and clarity, and the
same reference numerals denote the same elements. As used herein,
the term "and/or" includes any and all combinations of one or more
of the associated listed items.
[0042] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
exemplary embodiments of the present invention. As used herein, the
singular forms "a", "an" and "the" are intended to include the
plural forms as well, unless the context clearly indicates
otherwise. It will be further understood that the terms
"comprises", "comprising,", "includes" and/or "including", when
used herein, specify the presence of stated features, integers,
steps, operations, elements, and/or components, but do not preclude
the presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof.
[0043] It will be understood that, although the terms first,
second, third etc. may be used herein to describe various elements,
components, regions, layers, and/or sections, these elements,
components, regions, layers, and/or sections should not be limited
by these terms. These terms are only used to distinguish one
element, component, region, layer, or section from another region,
layer, or section. Thus, a first element, component, region, layer,
or section discussed below could be termed a second element,
component, region, layer, or section without departing from the
teachings of exemplary embodiments.
[0044] The embodiments of the present invention provide an
electrode assembly including an electrode including a plurality of
fibrous structures which may increase an interfacial surface area
between electrodes as compared to a conventional two-dimensional
(2D) battery structure in which a plate-type anode and a plate-type
cathode face each other.
[0045] When the expression `different direction` is used herein, it
means that when an anode including a plurality of fibrous
structures and a cathode including a plurality of fibrous
structures are stacked or wound to form an electrode structure, the
fibrous structures of any one electrode extend in an arbitrary
direction other than a direction in which the fibrous structures of
the other electrode extend. That is, the plurality of fibrous
structures constituting the anode and the cathode may have
structural flexibility high enough to be arranged at various angles
and in various directions.
[0046] Also, when the expression `cross each other` is used herein,
it means that when an anode including a plurality of fibrous
structures and a cathode including a plurality of fibrous
structures are stacked or wound to form an electrode structure, the
fibrous structures of the anode and the cathode are arranged to
have at least one point where they meet each other, which is
different from a conventional structure in which an anode and a
cathode are stacked or arranged in the same direction.
[0047] Also, when the term `separator` is used herein, the
separator includes a separator that is generally commonly used in a
liquid electrolyte battery using a liquid electrolyte having
affinity with the separator. Furthermore, when the separator used
herein includes an intrinsic solid polymer electrolyte and/or a gel
solid polymer electrolyte which is so strongly bound to the
separator that the electrolyte and the separator are recognized as
the same. Accordingly, the meaning of the separator has to be
defined as described herein.
[0048] FIG. 1 is a perspective view illustrating an electrode
assembly 100 of a battery, according to an embodiment of the
present invention. FIG. 2 is a perspective cross-sectional view
illustrating first and second structures 111 and 121 having fibrous
shapes, according to an embodiment of the present invention.
[0049] Referring to FIG. 1, the electrode assembly 100 constituting
the battery includes a plurality of the first and second structures
111 and 121 and a separator 130. The first structures 111 may
extend in parallel, and the second structures 121 may extend in
parallel. The first structures 111 may extend in an x direction,
and the second structures 121 may extend in a y direction different
from the x direction.
[0050] The first structures 111 and/or the second structures 121
may extend in parallel to be spaced apart from one another by a
distance `d` as shown in FIG. 1. Each of the first structures 111
and/or the second structures 121 may have a thickness w enough to
provide forming processability suitable for various arrangements of
the first and second structures 111 and 121. For example, the
thickness w of the first and second structures 111 and 121 may
range from 400 .mu.m to 2,000 .mu.m, and may be appropriately
determined according to a field to which the battery is applied.
The distance d may be greater than 0 .mu.m and less than 1,000
.mu.m, and preferably, from 2 .mu.m to 400 .mu.m. As described
below, in order to increase an interfacial surface area between
electrodes, the distance d may be greater than 0 .mu.m and less
than the thickness w of the first and second structures 111 and
121.
[0051] The first structures 111 extending in one direction in
parallel may be electrically connected to one another to constitute
one electrode, for example, a cathode 110. Likewise, the second
structures 121 may be electrically connected to one another to
constitute another electrode having a different polarity, for
example, an anode 120.
[0052] Although the first structures 111 and the second structures
121 extend perpendicular to each other in FIG. 1, the present
embodiment is not limited thereto. For example, the first and
second structures 111 and 121 having fibrous shapes may extend with
an angle of about 45.degree. or 60.degree. therebetween.
[0053] Referring to FIG. 2, the first and second structures 111 and
121 may include anode and cathode current collector cores 112a and
112b and anode and cathode active material layers 113a and 113b
that surround the anode and cathode current collector cores 112a
and 112b. The anode and cathode active material layers 113a and
113b may be respectively coated on the anode and cathode current
collector cores 112a and 112b with slurries including a
corresponding active material, a binder, and a conductive material.
Each of the slurries may include the corresponding active material
in an amount of 80 to 98 wt %, the binder in an amount of 1 to 10
wt %, and the conductive material in an amount of 1 to 10 wt %
based on 100 wt %.
[0054] A thickness of the anode active material layer 113a may
range from 1 .mu.m to 300 .mu.m, and preferably, from 30 .mu.m to
100 .mu.m. A thickness of the cathode active material layer 113b
may range from 3 .mu.m to 100 .mu.m, and preferably, from 3 .mu.m
to 40 .mu.m, and more preferably, from 5 .mu.m to 20 .mu.m. Since a
thickness of the cathode active material layer 113b is determined
in the aforesaid range, the battery may ensure high output and may
be made very thin. When a thickness of the cathode active material
layer 113b is less than 3 .mu.m, the effect of retarding internal
short-circuit may be degraded, and when the battery is a
lithium-ion secondary battery, high output may not be ensured.
Also, when a thickness of the cathode active material layer 113b is
greater than 100 .mu.m, the battery may not be made thin.
[0055] The anode and cathode current collector cores 112a and 112b
may be, for example, soft metal lines. For example, the cathode
current collector core 112a may be formed of a metal-based material
such as stainless steel, titan, aluminum, or an alloy thereof.
Preferably, the cathode current collector core 112a may be formed
of aluminum or an alloy thereof. The anode current collector core
112b may be formed of a metal-based material such as copper,
stainless steel, nickel, or an alloy thereof. Preferably, the anode
current collector core 112b may be formed of copper or an alloy
thereof.
[0056] However, the present embodiment is not limited thereto, and
each of the cathode and anode current collector cores 112a and 112b
may include a material whose shape may be easily changed, for
example, a polymer material having electronic conductivity such as
poly(sulfurnitrile), polypyrrole, poly(p-phenylene), poly(phenylene
sulfide), polyaniline, or Poly(p-phenylenevinylene). Alternatively,
each of the cathode and anode current collector cores 112a and 112b
may be formed of a fibrous material obtained by mixing a conductive
carbon paste, a nano metal particle paste, or an indium tin oxide
(ITO) paste with a binder.
[0057] Although the cathode and anode current collector cores 112a
and 112b of FIG. 2 have circular cross-sectional shapes in FIG. 2,
the present embodiment is not limited thereto. For example, the
cathode and anode current collector cores 112a and 112b may have
arbitrary shapes that may allow the cathode and anode active
material layers 113a and 113b to be easily attached to the anode
and cathode current collector cores 112a and 112b. For example, the
cathode and anode current collector cores 112a and 112b may have
predetermined surface roughnesses and arbitrary cross-sectional
shapes, for example, square or oval cross-sectional shapes, whose
surface curvature change ranges from 60% to 140%.
[0058] The active material layer 130 may include a material layer
suitable for a primary battery or a secondary battery. For example,
when the battery is a primary battery, the cathode active material
layer 113a may include manganese oxide, electrolytic manganese
dioxide (EMD), nickel oxide, lead oxide, lead dioxide, silver
oxide, iron sulfate, or conductive polymer particles, and the anode
active material layer 113b may include zinc, aluminum, iron, lead,
or magnesium particles.
[0059] When the battery is a secondary battery, the cathode active
material layer 113a may include a Li compound including at least
one metal of Ni, Co, Mn, Al, Cr, Fe, Mg, Sr, V, La, and Ce, and at
least one nonmetal element selected from the group consisting of O,
F, S, P and a combination thereof. For example, the cathode active
material layer 113a may include a compound represented by
LiaAl-bBbD2, where A is selected from the group consisting of Ni,
Co, Mn, and a combination thereof, B is selected from the group
consisting of Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth
element, and a combination thereof, and D is selected from the
group consisting of O, F, S, P, and a combination thereof, and
0.95.ltoreq.a.ltoreq.1.1 and 0.ltoreq.b.ltoreq.0.5.
[0060] When the battery is a secondary battery, the anode active
material layer 113b may include a carbon-based material such as a
low-crystallized carbon or high-crystallized carbon-based material
which can intercalate and deintercalate lithium ions. The
low-crystallized carbon may be soft carbon or hard carbon. The
high-crystallized carbon may be natural graphite or high
temperature baked carbon such as Kish graphite, pyrolytic carbon,
mesophase pitch-based carbon fiber, meso-carbon microbeads,
Mesophase pitches, or petroleum or coal tar pitch-derived cokes.
The anode active material layer 113b may include a binder, and the
binder may be a polymer material such as vinylidene
fluoride-hexfluoropropylene copolymer (PVDF-co-HFP),
polyvinylidenefluoride, polyacrylonitrile, or
polymethylmethacrylate. Alternatively, in order to provide a
high-capacity secondary battery, the cathode active material layer
113b may include a metal-based or intermetallic compound including
S, Si, or Sn.
[0061] Although the current collector cores 112a and 112b and the
active material layers 113a and 113b are separately formed in FIG.
2, the present embodiment is not limited thereto: any current
collector core and a corresponding active material layer of at
least one of the first structures 111 and the second structures 121
may be formed of the same material.
[0062] In one example, only one of the first and second structures
111 and 121 may further include a solid electrolyte layer such as
an intrinsic solid polymer electrolyte layer. The solid electrolyte
layer may be formed by using a consecutive impregnation process
using the same solvent as that used to form an active material
layer disposed under the solid electrolyte layer. The solid
electrolyte layer may include, for example, a polymer matrix
composed of any one of polyethylene, polypropylene, polyimide,
polysulfone, polyurethane, polyvinyl chloride, polystyrene,
polyethylene oxide, polypropylene oxide, polybutadiene, cellulose,
carboxymethyl cellulose, nylon, polyacrylonitrile, polyvinylidene
fluoride, polytetrafluoroethylene, a copolymer of vinylidene
fluoride and hexafluoropropylene, a copolymer of vinylidene
fluoride and trifluoroethylene, a copolymer of vinylidene fluoride
and tetrafluoroethylene, polymethylacrylate, polyethylacrylate,
polymethylmethacrylate, polyethylmethacrylate, polybutylacrylate,
polybutylmethacrylate, polyvinyl acetate, polyvinyl alcohol, and a
combination thereof, an additive, and an electrolytic solution. The
additive may be silica, talc, alumina (Al2O3), TiO2, clay, zeolite,
or a combination thereof. The electrolytic solution may be an
aqueous electrolytic solution including salt such as potassium
hydroxide (KOH), potassium bromide (KBr), potassium chloride (KCL),
zinc chloride (ZnCl2), or sulfuric acid (H2SO4).
[0063] In FIG. 2, only the second structures 121 further each
include a solid electrolyte layer 114 such as an intrinsic solid
polymer electrolyte. As such, since the solid electrolyte layer 114
is formed on structures of any of the cathode 110 and the anode
120, a volume may be reduced when compared to a case where the
solid electrolyte layer 114 is formed on structures of both the
cathode 110 and the anode 120, thereby further improving energy
density. Also, assuming that the first structures 111 of the
cathode 110 and the second structures 121 of the anode 120 cross
each other, if the solid electrolyte layer 114 is formed on both
the cathode 110 and the anode 120, cracks may occur in the solid
electrolyte layer 114 due to a change in a volume of the electrode
assembly 100 while a secondary battery is charged or discharged,
thereby reducing the lifetime of the electrode assembly 100.
Accordingly, preferably, the solid electrolyte layer 114 may be
selectively formed only on the structures of one electrode whose
volume change is smaller during its charging/discharging than other
electrode. For example, when the battery is a secondary battery,
the solid electrolyte layer 114 may be selectively formed only on
the second structures 121 of the anode 120 whose volume change is
relatively small during charging/discharging as shown in FIG.
2.
[0064] Referring back to FIG. 1, the separator 130 may have a
layered shape, and is disposed between the first structures 111
constituting the cathode 110 and the second structures 121
constituting the anode 120. The separator 130 may be, for example,
a micro-porous film, a woven fabric, a nonwoven fabric, an
intrinsic solid polymer electrolyte film, or a gel solid polymer
electrolyte film. The intrinsic solid polymer electrolyte film may
include a straight chain polymer material or a cross-linked polymer
material. The gel polymer electrolyte film may be any one of a
plasticizer-containing polymer including salt, a filler-containing
polymer, and a pure polymer, or a combination thereof.
[0065] The above-listed materials for the separator 130 are
exemplary, and any appropriate electronic insulating material whose
shape may be easily changed and have appropriate ionic
conductivity, and which has high mechanical strength and may not be
broken or cracked even when the electrode assembly 100 is deformed
may be used for the separator 130. The separator 130 may be a
single-layered film or a multi-layered film. The multi-layered film
may be a stack of single-layered films formed of the same material
or a stack of films formed of different materials. A thickness of
the separator 130 may range from 10 .mu.m to 300 .mu.m, preferably,
from 10 .mu.m to 40 .mu.m, and more preferably, from 10 .mu.m to 25
.mu.m in consideration of durability, shut-down function, and
battery stability.
[0066] As described above, the first structures 111 constituting
the cathode 110 and the second structures 121 constituting the
anode 120 extend in different directions, and cross each other in
different directions with the separator 130 therebetween. Since the
first and second structures 111 and 121 of the cathode 110 and the
anode 120 have curved surfaces and are arranged in a
three-dimensional (3D) manner and cross each other with the
separator 130 therebetween, an interfacial surface area between the
cathode 110 and the anode 120 may be increased. As a result, energy
density in the same volume may be improved, and charge/discharge
speed, charge/discharge efficiency, and battery cycle
characteristics may also be improved.
[0067] FIG. 3 is a perspective view illustrating an electrode
assembly 200 of a battery, according to another embodiment of the
present invention.
[0068] Referring to FIG. 3, the electrode assembly 200 includes a
plurality of first through fourth structures 111a, 121a, 121b, and
111b having fibrous shapes, and the separator 130. The first
structures 111a and the second structures 121a which extend in
parallel in one direction correspond to the first and second
structures 111 and 121 of the electrode assembly 100 illustrated in
FIG. 1. The first and second structures 111a and 121a are coupled
to each other and may respectively constitute a first cathode 110a
and a first anode 120a of the battery.
[0069] The electrode assembly 200 of FIG. 3 further includes the
third structures 121b that have fibrous shapes and extend on a
first main surface 130a of the separator 130 in the same direction
as the first structures 111a to alternate with the first structures
111a. Likewise, the electrode assembly 200 may further include the
fourth structures 111b that have fibrous shapes and extend on a
second main surface 130b of the separator 130 in the same direction
as the second structures 121a of the anode 120a to alternate with
the second structures 121a.
[0070] The third structures 121b and the fourth structures 111b may
have respectively polarity opposite to that of the first structures
111a and the second structures 121a which are respectively adjacent
to the third structures 121b and the fourth structures 111b. For
example, the third structures 121b may constitute a second anode
120b and the fourth structures 111b may constitute a second cathode
110b.
[0071] The first cathode 110a and the second cathode 110b may be
coupled to each other with leads to constitute one single common
cathode. Likewise, the first anode 120a and the second anode 120b
may be electrically coupled to each other to constitute one single
common anode. However, it is exemplary and the present embodiment
is not limited thereto. For example, any one of the first cathode
110a and the second cathode 110b and any one of the first anode
120a and the second anode 120b may be coupled to each other, and
the remaining cathode and anode may be provided as external
electrodes to provide a bipolar battery. Also, it would be
understood by one of ordinary skill in the art that any of various
bipolar batteries for increasing an operating voltage may be
provided by appropriately selecting the number and arrangement of
structures having opposite polarities, coupling the structures in
series in the battery, and providing remaining structures as a
cathode and an anode.
[0072] In order to ensure stable insulation between adjacent
structures having opposite polarities, some of the first through
fourth structures 111a, 121a, 121b, and 111b may be partially
buried in the first and second main surfaces 130a and 130b of the
separator 130 as shown in FIG. 3. To this end, trenches T (see FIG.
5) for receiving the first through fourth structures 111a, 121a,
121b, and 111b may be formed in the first and second main surfaces
130a and 130b of the separator 130, or the first through fourth
structures 111a, 121a, 121b, and 111b may be buried in the first
and second main surfaces 130a and 130b of the separator 130 by
pressing the first through fourth structures 111a, 121a, 121b, and
111b after the first through fourth structures 111a, 121a, 121b,
and 111b are disposed.
[0073] As described with reference to FIG. 2, a solid electrolyte
layer may be further formed only on an active material layer of
structures having one type of polarity. In this case, adjacent
structures having opposite polarities may extend on the same
surface of the separator 130 while contacting each other without
being spaced apart from each other. For example, in FIG. 3, a solid
electrolyte layer may be selectively formed only on one of the
second structures 111a and the third structures 121b, and the
second structures 111a and the third structures 121b may be
arranged in parallel on the first main surface 130a of the
separator 130 without being spaced apart from each other. Likewise,
a solid electrolyte layer may be selectively formed only on one of
the second structures 121a and the fourth structures 111b, and in
this case, the second structures 121a and the fourth structures
111b may be arranged in parallel on the second main surface 130b of
the separator 130 without being spaced apart from each other.
[0074] In FIG. 3, since the first through fourth structures 111a,
121a, 121b, and 111b having 3D curved surfaces are disposed such
that structures having opposite polarities face each other by
crossing each other with the separator 130 therebetween and also
face each other on the same main surface of the separator 130, an
interfacial surface area between electrodes may be increased as
compared to that of a simple conventional planer electrode
assembly. Accordingly, energy density in the same volume may be
improved, and charge/discharge speed, charge/discharge efficiency,
and battery cycle characteristics may also be improved.
[0075] FIG. 4 is an exploded perspective view illustrating an
electrode assembly 300 of a battery, according to another
embodiment of the present invention.
[0076] Referring to FIG. 4, the electrode assembly 300 includes
first and second separators 130a and 130b which are stacked.
Although the first separator 130a and the second separator 130b are
illustrated in FIG. 4, the present embodiment is not limited
thereto and three or more separators may be stacked.
[0077] In the electrode assembly 300, the first structures 111a
constituting a first electrode 310a, the second structures 121a
constituting a second electrode 320a, and the first separator 331
are the same as those described with reference to FIG. 1. Third
structures 121c on a main surface of the second separator 332 which
is opposite to an interface between the first separator 331 and the
second separator 332, extend in a direction, for example, a y
direction, to cross the first structures 111a extending in, for
example, an x direction.
[0078] Also, the third structures 121c may have polarity opposite
to that of the first structures 111a. For example, when the first
electrode 310a is a cathode, the third structures 121c may be
coupled to one another to constitute a second anode 320c. The
second electrode 320a (referred to as a first anode) and the second
anode 320c may be coupled to each other to constitute one common
anode. Although not shown in FIG. 4, another separator may be
stacked over the second separator 332, and the first electrode 310a
(referred to as a first cathode) may be coupled to structures of a
cathode on the another isolation form stacked on the second
separator 332 to constitute one common cathode. The structure is
exemplary, and a bipolar battery may be provided by appropriately
determining the number and arrangement of structures having
opposite polarities and coupling the structures.
[0079] FIG. 5 is an exploded perspective view illustrating an
electrode assembly 400 of a battery, according to another
embodiment of the present invention.
[0080] Referring to FIG. 5, the electrode assembly 400 includes a
plurality of separators, that is, first and second separators 431
and 432 which are stacked. Although the first separator 431 and the
second separator 432 are illustrated in FIG. 5, three or more
separators may be stacked.
[0081] In the electrode assembly 400, for the first through fourth
structures 111a, 121a, 121b, and 111b respectively constituting
electrodes 410a, 420a, 420b, and 410b, the disclosure with
reference to FIG. 3 may be referred to. Additional Fifth and sixth
structures 111c and 121c, which extend on a main surface of the
second separator 432 which is opposite to interface between the
first separator 431 and the second separator 432, extend in a
direction, for example, a y direction, to cross the first
structures 111a and the third structures 121b disposed under the
fifth and sixth structures 111c and 121c. The fifth and sixth
structures 111c and 121c have opposite polarities, and may be
disposed on the main surface of the second separator 432 to
alternate with each other.
[0082] As described above with reference to FIG. 3, a solid
electrolyte layer may be further formed only on an active material
layer of each of structures having one polarity. In this case,
adjacent structures having opposite polarity may extend on the same
main surface of the first and second separators 431 and 432 by
contacting each other without being spaced apart from each
other.
[0083] Also, a cathode 410c and an anode 420c may be provided by
appropriately combining groups of structures having different stack
orders and extension directions, or a bipolar battery may be
provided by selecting some of structures and electrically coupling
the structures as described above. As in FIGS. 4 and 5, since two
or more separators are stacked and fibrous structures are arranged
on interface and a main surface of the separators opposite to the
interface, an interfacial electrode area between adjacent
structures having opposite polarities is increased, thereby
improving energy density, charge/discharge speed, charge/discharge
efficiency, and battery cycle characteristics.
[0084] FIGS. 6A through 6C are perspective views illustrating an
electrode assembly 500 according to another embodiment of the
present invention.
[0085] Referring to FIGS. 6A and 6B, each of a cathode 510M and an
anode 520M of the electrode assembly 500 includes a plurality of
fibrous structures which have the same polarity and cross each
other. The plurality of fibrous structures 511x and 511y and 521w
and 521z having the same polarity may contact each other and may
form grid structures, respectively. For example, the cathode 510M
includes the plurality of fibrous structures 511x that extend in an
x direction, and the plurality of fibrous structures 511y that
extend in another direction, that is, a y direction, to cross the
structures 511x. The anode 520M includes the plurality of fibrous
structures 521w and 521z which extend in different directions, that
is, a w direction and a z direction, and cross each other.
[0086] In the electrode assembly 500 of FIG. 6C, a first separator
531 is disposed between the cathode 510M and the anode 520M, to
electrically isolate the cathode 110M and the anode 120M. The
cathode 510M and the anode 520M may be aligned to be symmetrical
with each other about the first separator 531. Alternatively, as
shown in FIG. 6C, the grid structures of the electrode 510M and
520M may be rotated such that the cathode 510M and the anode 520M
cross each other without being symmetrical with each other. That
is, the cathode 510M may be disposed such that the structures 511x
and 511y are aligned in the w and z directions, and the anode 520M
may be disposed such that the structures 521w and 521z are aligned
in the x and y directions. In this case, an interfacial area
between structures may be increased when compared to a case where
the cathode 510M and the anode 520M are accurately aligned with
each other.
[0087] In other example, the cathode 510M and the anode 520M may be
aligned in the same direction and their grid structures may be
misaligned. For example, although not shown in FIGS. 6A through 6C,
the cathode 510M and the anode 520M may be offset such that both
the structures 511x and 511y of the cathode 510M and the structures
521w and 521z of the anode 520M may be arranged in the x and y
directions, and any one of the cathode 510M and the anode 520M may
be moved in the x direction or the y direction to misalign the grid
structures. Also, an interfacial area may be increased by combining
the aforesaid rotation method and the movement method to misalign
the grid structures of the cathode 510M and the anode 120M.
[0088] In another example, as shown in FIG. 6C, a second separator
532 may be stacked over the first separator 531, and an electrode
530M having another grid structure may be disposed on a main
surface of the second separator 532 which is opposite to interface
between the first separator 531 and the second separator 532.
Accordingly, energy density may be further improved. The additional
electrode 530M may be an anode, and the electrode 530M and the
cathode 510M disposed under the electrode 530M may be aligned in
such a manner as that described for the alignment of the cathode
510M and the anode 520M.
[0089] FIG. 7 is a perspective view illustrating an electrode
assembly 600 of a battery, according to another embodiment of the
present invention.
[0090] Referring to FIG. 7, in the electrode assembly 600, the
first structures 111 constituting a first electrode 610 and the
second structures 121 constituting a second electrode 620 cross
each other as weft threads and warp threads reciprocating through a
separator 630. The right image illustrates the electrode assembly
600 from which the separator 630 is not shown in order to clearly
show the first structures 111 and the second structures 121.
[0091] Since different structures are insulated by the separator
630, even when the electrode assembly 600 is deformed, the first
and second structures 111 and 121 may be prevented from being
short-circuited. Energy density may be improved and insulation
between the first and second structures 111 and 121 may be improved
by forming a solid electrolyte layer only on structures having one
polarity as described with reference to FIG. 2. Although not shown
in FIG. 7, one or more separators may be further stacked over the
separator 630 without departing from the scope of the present
invention.
[0092] Also, as described above, when the first and second
structures 111 and 121 having fibrous structures cross each other
in different directions, the first and second structures 111 and
121 may cross each other at a predetermined frequency, or at least
some of the first and second structures 111 and 121 may cross each
other at random. Since structures having one polarity are at least
partially buried in structures having opposite polarity, an
interfacial area between the first electrode 610 and the second
electrode 620 may be increased, energy density may be improved, and
charge/discharge speed, charge/discharge efficiency, and lifetime
may also be improved.
[0093] FIG. 8 is a perspective view illustrating an electrode
assembly 700 according to another embodiment of the present
invention.
[0094] Referring to FIG. 8, the electrode assembly 700 includes,
instead of a separator, an isolation matrix 730 that has a
thickness great enough for at least two electrodes 710 and 720
respectively including first and second structures 711 and 712
having opposite polarities to be embedded in the isolation matrix
730. The isolation matrix 730 may be formed of the same material as
those of the separators in the previous embodiments. In order to
align the first and second structures 711 and 712 in the isolation
matrix 730, the isolation matrix 730 may be provided by aligning
the first and second structures 711 and 722 in a solution that is
to be an isolation matrix and then coagulating the solution. The
isolation matrix 730 may be formed of an intrinsic solid polymer
electrolyte or a gel polymer electrolyte.
[0095] The first structures 711 passing through the isolation
matrix 730 and extending in an x direction may be disposed on the
same plane. Likewise, the second structures 721 passing through the
isolation matrix 730 and extending in a y direction may be disposed
on the same plane. The planes on which the first and second
structures 711 and 712 having opposite polarities are disposed are
spaced apart from each other, and the first and second structures
711 and 721 are separated from each other in the isolation matrix
730.
[0096] It would be understood by one of ordinary skill in the art
that the first and second structures 711 and 721 passing through
the isolation matrix 730 may be stacked as two or more layers in
the isolation matrix 730, and two or more isolation matrixes 730
may be stacked. Since an interfacial area between the first and
second structures 711 and 722 which are adjacent to each other is
increased in a 3D manner, energy density may be improved, and
charge/discharge efficiency and battery cycle characteristics may
also be improved.
[0097] Although structures having opposite polarities are spaced
apart in FIG. 8, a solid electrolyte layer such as an intrinsic
solid polymer electrolyte layer may be further formed only on the
structures having a specific one of two polarities, for example,
the structures of an anode. In this case, structures having
opposite polarities may extend to cross in the same direction or
different directions without being spaced apart from each other.
Alternatively, structures having the same polarities may extend to
cross in the same direction or different directions by contacting
each other without being spaced apart from each other.
[0098] FIG. 9 is a perspective view illustrating an electrode
assembly 800 according to another embodiment of the present
invention.
[0099] Referring to FIG. 9, the electrode assembly 800 includes an
isolation matrix 830 that has a thickness great enough for first
through fourth structures 711a, 721a, 721b, and 711b having
different polarities to be stacked to cross each other in the
isolation matrix 830. In order to align the first through fourth
structures 811a, 821a, 821b, and 811b in the isolation matrix 830,
the isolation matrix 830 may be provided by aligning the first
through fourth structures 811a, 821a, 821b, and 811b in a solution
that is to be an isolation matrix and then coagulating the
solution. The isolation matrix 830 may be formed of a solid polymer
electrolyte or a gel polymer electrolyte.
[0100] The first through fourth structures 811a, 821a, 821b, and
811b pass through the isolation matrix 830. The electrode assembly
800 is different from the electrode assembly 700 in that the
electrode assembly 800 further includes the third structures 821b
that extend in an x direction on the same plane as the first
structures 811a extending in the x direction to alternate with the
first structures 811a and have polarity opposite to polarity of the
first structures 811a. Likewise, the electrode assembly 800 further
includes the fourth structures 811b that extend in a y direction on
the same plane as the second structures 821a passing through the
isolation matrix 830 and extending in the y direction to alternate
with the second structures 821a and have polarity opposite to
polarity of the second structures 821a. One cathode and an anode
may be provided outside a battery by combining structures having
the same polarity, or a bipolar battery may be provided by coupling
structures having opposite polarities in the battery.
[0101] The embodiments may be combined unless being contradictory
without departing from the scope of the invention. For example, in
the electrode assembly 600 of FIG. 7, the isolation matrix 730 (see
FIG. 8) may be used instead of the separator 630, and the first and
second structures 111 and 121 which are weft threads and warp
threads illustrated in the right image of FIG. 7 may be buried as
at least one layer in the isolation matrix 730. Also, in the
electrode assembly 500 of FIG. 6C, the first and second structures
511x and 511y may cross each other as weft threads and warp
threads, and the third and fourth structures 521w and 521z may
cross each other as weft threads and warp threads. In this case, a
solid electrolyte layer may be selectively further formed only on
any one electrode, preferably, an electrode whose volume change
during charging/discharging is the smaller electrode among the
cathode 510M including the structures 511x and 511y and the anode
520M including the structures 521w and 521z. Also, it would be
understood that two or more structures having different
arrangements may be combined.
[0102] FIG. 10 is a perspective view illustrating an electrode
assembly 900 according to another embodiment of the present
invention.
[0103] Referring to FIG. 10, the electrode assembly 900
constituting a battery includes a first electrode 920 including a
plurality of first structures 121 having fibrous shapes, and a
second electrode 910 having a planner shape and a polarity opposite
to polarity of the first structures 121. The second electrode 910
facing the first electrode 920 including the first structures 121
is different from other fibrous structures in that the second
electrode 910 has a planner shape.
[0104] A thickness w of each of the first structures 121 may range
from 400 .mu.m to 2,000 .mu.m, and may be appropriately determined
according to a field to which the battery is applied. A distance d
between the first structures 121 may be greater than 0 .mu.m and
less than 1,000 .mu.m, and preferably from 2 .mu.m to 400 .mu.m. In
order to increase an interfacial surface area between the first and
second electrodes 920 and 910, the distance d may be greater than 0
.mu.m and less than the thickness w of each of the first structures
121.
[0105] A separator 930 is provided between the first electrode 910
and the second electrodes 920. The separator 930 may be a
micro-porous film, a woven fabric, a nonwoven fabric, an intrinsic
solid polymer electrolyte film, or a gel solid polymer electrolyte
film as described above. The intrinsic solid polymer electrolyte
film may include a straight chain polymer material or a
cross-linked polymer material. The gel polymer electrolyte film may
be any one of a plasticizer-containing polymer including salt, a
filler-container polymer, and a pure polymer, or a combination
thereof.
[0106] The first structures 121 extending in parallel in one
direction may be electrically connected to one another to
constitute one electrode, for example, a cathode. In this case, the
second electrode 910 having the planner shape may be an anode.
[0107] FIG. 11 is a perspective view illustrating an electrode
assembly 1000 according to another embodiment of the present
invention.
[0108] Referring to FIG. 11, the electrode assembly 1000 is
different from the electrode assembly 1000 of FIG. 10 in that the
first structures 121 further extend to surround a second electrode
1010 and thus to face both main surfaces of the second electrode
1010 having a planner shape. In order to separate a first electrode
1020 including the first structures 121 from the second electrode
1010 having the planner shape, separators 1030a and 1030b may be
disposed between the first structures 121 and the both main
surfaces of the second electrode 1010. A plurality of separators
may be provided as shown in FIG. 11, and one planner separator may
be folded to contact the both main surfaces of the second electrode
1010. Alternatively, a separator may be provided by providing an
intrinsic solid polymer electrolyte or a gel solid polymer
electrolyte to surround the second electrode 1010.
[0109] Since the first structures 121 are wound around the both
main surfaces of the second electrode 1010, an interfacial surface
area between the first and second electrodes 10120 and 1010 may be
increased. Accordingly, energy density in the same volume may be
improved, and charge/discharge efficiency and battery cycle
characteristics may also be improved. Although the first structures
121 surround the second electrode 1010 by being wound one time in
FIG. 11, the first structures 121 may be wound two or more times
without departing from the scope of the present invention. In this
case, only one first structure, instead of a plurality of first
structures, may be provided by being spirally wound.
[0110] FIG. 12 is a perspective view illustrating an electrode
assembly 1100 according to another embodiment of the present
invention.
[0111] Referring to FIG. 12, an electrode 1121M of the electrode
assembly 1100 includes a plurality of fibrous structures 1121x and
1121y having the same polarity and crossing each other. The
plurality of fibrous structures 1121x and 1121y having the same
polarity may contact each other to form a grid structure. Another
electrode 1110 of the electrode assembly 1000 has a planner shape
like the second electrode 910 of FIG. 10. The electrode 1121M may
be an anode and the electrode 1110 may be a cathode. A separator
1130 is provided between the electrode 1121M including the
structures 1121x and 1121y and the electrode 1110 having the
planner shape.
[0112] FIG. 13 is a perspective view illustrating an electrode
assembly 1200 according to another embodiment of the present
invention.
[0113] Referring to FIG. 13, the electrode assembly 1200 includes
first structures 121a and further includes second structures 121b
that extend in a direction different from a direction in which the
first structures 121a extend to cross the first structures 121a and
have the same polarity as that of the first structures 121a, when
compared to the electrode assembly 1100 of FIG. 12. However, in
FIG. 13, the first structures 121a and the second structures 121b
cross each other as weft threads and warp threads.
[0114] Another electrode 1210 of the electrode assembly 1200 has a
planner shape. The electrode 1210 is a cathode, and the electrode
1220 including the first and second structures 121a and 121b is an
anode. A separator 1230 is provided between the electrode 1210
having the planner shape and the electrode 1220 including the
structures 121a and 121b.
[0115] After electrode assemblies are formed, a separator or an
isolation matrix may be impregnated in an appropriate electrolyte
to be activated. Alternatively, when the separator or the isolation
matrix is formed of a gel or intrinsic solid polymer electrolyte,
the separator or the isolation matrix may be activated without
being impregnated.
[0116] As described above, since at least one of a cathode and an
anode includes a plurality of fibrous structures, an interfacial
surface area between electrodes may be increased and an electrode
assembly which is thin and whose shape is easily changed may be
easily made. It would be understood by one of ordinary skill in the
art that the embodiments may be combined unless being contradictory
without departing from the scope of the present invention. For
example, in FIG. 13, first and second structures crossing each
other as weft threads and warp threads may extend to reciprocate
through a separator.
[0117] A battery whose shape is easily changed may be provided by
changing shapes of fibrous structures whose shapes may be easily
changed, adjusting areas of the structures to adjust capacity, and
folding, bending, or stacking the structures. For example, the
battery may be used as a small battery by being attached to
clothes, bags, etc., or may be used as a large or medium battery of
vehicles by having high capacity.
[0118] Also, according to the embodiments, since a interfacial area
is increased in a 3D manner and charge/discharge efficiency is
improved, a battery may be manufactured by using a small amount of
cathode material. In the case of a lithium ion battery, considering
its limited reserves, according to the embodiments, a battery that
may obtain the same energy with less lithium may be provided.
[0119] While the present invention has been particularly shown and
described with reference to exemplary embodiments thereof, it will
be understood by those of ordinary skill in the art that various
changes in form and details may be made therein without departing
from the spirit and scope of the present invention as defined by
the following claims.
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